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1.
Cell ; 152(5): 1008-20, 2013 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-23452850

RESUMO

Metazoan evolution involves increasing protein domain complexity, but how this relates to control of biological decisions remains uncertain. The Ras guanine nucleotide exchange factor (RasGEF) Sos1 and its adaptor Grb2 are multidomain proteins that couple fibroblast growth factor (FGF) signaling to activation of the Ras-Erk pathway during mammalian development and drive embryonic stem cells toward the primitive endoderm (PrE) lineage. We show that the ability of Sos1/Grb2 to appropriately regulate pluripotency and differentiation factors and to initiate PrE development requires collective binding of multiple Sos1/Grb2 domains to their protein and phospholipid ligands. This provides a cooperative system that only allows lineage commitment when all ligand-binding domains are occupied. Furthermore, our results indicate that the interaction domains of Sos1 and Grb2 have evolved so as to bind ligands not with maximal strength but with specificities and affinities that maintain cooperativity. This optimized system ensures that PrE lineage commitment occurs in a timely and selective manner during embryogenesis.


Assuntos
Embrião de Mamíferos/metabolismo , Células-Tronco Embrionárias/metabolismo , Proteína Adaptadora GRB2/metabolismo , Proteína SOS1/metabolismo , Sequência de Aminoácidos , Animais , Linhagem da Célula , Endoderma/metabolismo , Eucariotos/genética , Eucariotos/metabolismo , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Fatores ras de Troca de Nucleotídeo Guanina/metabolismo
2.
Clin Proteomics ; 21(1): 13, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38389037

RESUMO

SARS-CoV-2 infection triggers extensive host immune reactions, leading to severe diseases in certain individuals. However, the molecular basis underlying the excessive yet non-productive immune responses in severe COVID-19 remains incompletely understood. In this study, we conducted a comprehensive analysis of the peripheral blood mononuclear cell (PBMC) proteome and phosphoproteome in sepsis patients positive or negative for SARS-CoV-2 infection, as well as healthy subjects, using quantitative mass spectrometry. Our findings demonstrate dynamic changes in the COVID-19 PBMC proteome and phosphoproteome during disease progression, with distinctive protein or phosphoprotein signatures capable of distinguishing longitudinal disease states. Furthermore, SARS-CoV-2 infection induces a global reprogramming of the kinome and phosphoproteome, resulting in defective adaptive immune response mediated by the B and T lymphocytes, compromised innate immune responses involving the SIGLEC and SLAM family of immunoreceptors, and excessive cytokine-JAK-STAT signaling. In addition to uncovering host proteome and phosphoproteome aberrations caused by SARS-CoV-2, our work recapitulates several reported therapeutic targets for COVID-19 and identified numerous new candidates, including the kinases PKG1, CK2, ROCK1/2, GRK2, SYK, JAK2/3, TYK2, DNA-PK, PKCδ, and the cytokine IL-12.

3.
J Urol ; 209(1): 187-197, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36067387

RESUMO

PURPOSE: This study aimed to evaluate the usefulness of the LDN-PSA (LacdiNAc-glycosylated-prostate specific antigen) in detecting clinically significant prostate cancer in patients suspected of having clinically significant prostate cancer on multiparametric magnetic resonance imaging. MATERIALS AND METHODS: Patients with prostate specific antigen levels ranging between 3.0 ng/mL and 20 ng/mL and suspicious lesions with PI-RADS (Prostate Imaging-Reporting and Data System) category ≥3 were included prospectively. The LDN-PSA was measured using an automated 2-step Wisteria floribunda agglutinin lectin-anti-prostate specific antigen antibody sandwich immunoassay. RESULTS: Two hundred four patients were included. Clinically significant prostate cancer was detected in 105 patients. On multivariable logistic regression analysis, prostate specific antigen density (OR 1.61, P = .010), LDN-PSAD (OR 1.04, P = .012), highest PI-RADS category (3 vs 4, 5; OR 14.5, P < .0001), and location of the lesion with highest PI-RADS category (transition zone vs peripheral zone) (OR 0.34, P = .009) were significant risk factors for detecting clinically significant prostate cancer. Among the patients with the highest PI-RADS category 3 (n=113), clinically significant prostate cancer was detected in 28 patients. On multivariable logistic regression analysis to predict the detection of clinically significant prostate cancer in patients with the highest PI-RADS category 3, age (OR 1.10, P = .026) and LDN-PSAD (OR 1.07, P < .0001) were risk factors for detecting clinically significant prostate cancer. CONCLUSIONS: LDN-PSAD would be a biomarker for detecting clinically significant prostate cancer in patients with prostate specific antigen levels ≤20 ng/mL and suspicious lesions with PI-RADS category ≥3. The use of LDN-PSAD as an adjunct to the use of prostate specific antigen levels would avoid unnecessary biopsies in patients with the highest PI-RADS category 3. Multi-institutional studies with large population are recommended.


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Humanos , Masculino , Imageamento por Ressonância Magnética , Neoplasias da Próstata/diagnóstico por imagem
4.
J Biol Chem ; 297(4): 101161, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34480897

RESUMO

Cell migration is an essential physiological process, and aberrant migration of epithelial cells underlies many pathological conditions. However, the molecular mechanisms governing cell migration are not fully understood. We report here that growth factor-induced epithelial cell migration is critically dependent on the crosstalk of two molecular switches, namely phosphorylation switch (P-switch) and transcriptional switch (T-switch). P-switch refers to dynamic interactions of deleted in liver cancer 1 (DLC1) and PI3K with tensin-3 (TNS3), phosphatase and tensin homolog (PTEN), C-terminal tension, and vav guanine nucleotide exchange factor 2 (VAV2) that are dictated by mitogen-activated protein kinase kinase 1/2-extracellular signal-regulated protein kinase 1/2-dependent phosphorylation of TNS3, PTEN, and VAV2. Phosphorylation of TNS3 and PTEN on specific Thr residues led to the switch of DLC1-TNS3 and PI3K-PTEN complexes to DLC1-PTEN and PI3K-TNS3 complexes, whereas Ser phosphorylation of VAV2 promotes the transition of the PI3K-TNS3/PTEN complexes to PI3K-VAV2 complex. T-switch denotes an increase in C-terminal tension transcription/expression regulated by both extracellular signal-regulated protein kinase 1/2 and signal transducer and activator of transcription 3 (STAT3) via interleukin-6-Janus kinase-STAT3 signaling pathway. We have found that, the P-switch is indispensable for both the initiation and continuation of cell migration induced by growth factors, whereas the T-switch is only required to sustain cell migration. The interplay of the two switches facilitated by the interleukin-6-Janus kinase-STAT3 pathway governs a sequence of dynamic protein-protein interactions for sustained cell migration. That a similar mechanism is employed by both normal and tumorigenic epithelial cells to drive their respective migration suggests that the P-switch and T-switch are general regulators of epithelial cell migration and potential therapeutic targets.


Assuntos
Movimento Celular/efeitos dos fármacos , Células Epiteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 2/genética , MAP Quinase Quinase 2/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
5.
Mol Cell ; 50(4): 565-76, 2013 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-23706821

RESUMO

Although Numb exhibits its tumor-suppressive function in breast cancer in part by binding to and stabilizing p53, it is unknown how the Numb-p53 interaction is regulated in cells. We found that Numb is methylated in its phosphotyrosine-binding (PTB) domain by the lysine methyltransferase Set8. Moreover, methylation uncouples Numb from p53, resulting in increased p53 ubiquitination and degradation. While Numb promotes apoptosis in a p53-dependent manner, the apoptotic function is abolished when Numb is methylated by Set8 or the Lys methylation sites in Numb are mutated. Conversely, the Numb-p53 interaction and Numb-mediated apoptosis are significantly enhanced by depletion of Set8 from cancer cells or by treating the cells with doxorubicin, a chemotherapeutic drug that causes a reduction in the mRNA and protein levels of Set8. Our work identifies the Set8-Numb-p53 signaling axis as an important regulatory pathway for apoptosis and suggests a therapeutic strategy by targeting Numb methylation.


Assuntos
Apoptose/fisiologia , Histona-Lisina N-Metiltransferase/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Sequência de Aminoácidos , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Sítios de Ligação/genética , Linhagem Celular , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Células HeLa , Histona-Lisina N-Metiltransferase/genética , Humanos , Immunoblotting , Lisina/genética , Lisina/metabolismo , Células MCF-7 , Proteínas de Membrana/genética , Metilação , Microscopia Confocal , Mutação , Proteínas do Tecido Nervoso/genética , Ligação Proteica , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteína Supressora de Tumor p53/genética
6.
Mol Cell Proteomics ; 18(2): 372-382, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30482845

RESUMO

Src homology 2 (SH2) domains play an essential role in cellular signal transduction by binding to proteins phosphorylated on Tyr residue. Although Tyr phosphorylation (pY) is a prerequisite for binding for essentially all SH2 domains characterized to date, different SH2 domains prefer specific sequence motifs C-terminal to the pY residue. Because all SH2 domains adopt the same structural fold, it is not well understood how different SH2 domains have acquired the ability to recognize distinct sequence motifs. We have shown previously that the EF and BG loops that connect the secondary structure elements on an SH2 domain dictate its specificity. In this study, we investigated if these surface loops could be engineered to encode diverse specificities. By characterizing a group of SH2 variants selected by different pY peptides from phage-displayed libraries, we show that the EF and BG loops of the Fyn SH2 domain can encode a wide spectrum of specificities, including all three major specificity classes (p + 2, p + 3 and p + 4) of the SH2 domain family. Furthermore, we found that the specificity of a given variant correlates with the sequence feature of the bait peptide used for its isolation, suggesting that an SH2 domain may acquire specificity by co-evolving with its ligand. Intriguingly, we found that the SH2 variants can employ a variety of different mechanisms to confer the same specificity, suggesting the EF and BG loops are highly flexible and adaptable. Our work provides a plausible mechanism for the SH2 domain to acquire the wide spectrum of specificity observed in nature through loop variation with minimal disturbance to the SH2 fold. It is likely that similar mechanisms may have been employed by other modular interaction domains to generate diversity in specificity.


Assuntos
Proteínas Proto-Oncogênicas c-fyn/química , Animais , Cristalografia por Raios X , Variação Genética , Humanos , Ligantes , Modelos Moleculares , Biblioteca de Peptídeos , Estrutura Secundária de Proteína , Proteínas Proto-Oncogênicas c-fyn/genética , Domínios de Homologia de src
7.
Mol Cell Proteomics ; 17(11): 2216-2228, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29217616

RESUMO

Cellular functions are frequently regulated by protein-protein interactions involving the binding of a modular domain in one protein to a specific peptide sequence in another. This mechanism may be explored to identify binding partners for proteins harboring a peptide-recognition domain. Here we report a proteomic strategy combining peptide and protein microarray screening with biochemical and cellular assays to identify modular domain-mediated protein-protein interactions in a systematic manner. We applied this strategy to Numb, a multi-functional protein containing a phosphotyrosine-binding (PTB) domain. Through the screening of a protein microarray, we identified >100 protein kinases, including both Tyr and Ser/Thr kinases, that could potentially interact with the Numb PTB domain, suggesting a general role for Numb in regulating kinase function. The putative interactions between Numb and several tyrosine kinases were subsequently validated by GST pull-down and/or co-immunoprecipitation assays. Furthermore, using the Oriented Peptide Array Library approach, we defined the specificity of the Numb PTB domain which, in turn, allowed us to predict binding partners for Numb at the genome level. The combination of the protein microarray screening with computer-aided prediction produced the most expansive interactome for Numb to date, implicating Numb in regulating phosphorylation signaling through protein kinases and phosphatases. Not only does the data generated from this study provide an important resource for hypothesis-driven research to further define the function of Numb, the proteomic strategy described herein may be employed to uncover the interactome for other peptide-recognition domains whose consensus motifs are known or can be determined.


Assuntos
Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Mapeamento de Interação de Proteínas , Proteínas Quinases/metabolismo , Motivos de Aminoácidos , Linhagem Celular Tumoral , Genoma Humano , Humanos , Proteínas de Membrana/química , Proteínas do Tecido Nervoso/química , Peptídeos/metabolismo , Fosforilação , Ligação Proteica , Domínios Proteicos , Reprodutibilidade dos Testes , Transdução de Sinais
8.
Int J Clin Oncol ; 25(4): 622-632, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31820210

RESUMO

BACKGROUND: The clinical impact of monitoring serum p53 antibodies, carbohydrate antigen19-9, and carcinoembryonic antigen in patients with colorectal cancer has not been fully evaluated. METHODS: A total of 420 surgically treated stage II/III colorectal cancer patients were retrospectively analyzed. Among them, 101 patients developed disease recurrence. The prognostic impact of preoperative and recurrence levels of serum p53 antibodies, carbohydrate antigen19-9, and carcinoembryonic antigen status was evaluated. RESULTS: Although preoperative carcinoembryonic antigen- and carbohydrate antigen19-9-positive status was significantly associated with recurrence, preoperative serum p53 antibody levels were not. Among two marker combinations, carcinoembryonic antigen + serum p53 antibodies showed the highest positive rate at recurrence. Although carcinoembryonic antigen and carbohydrate antigen19-9 frequently converted from preoperative-negative status to positive status at recurrence, serum p53 antibodies converted to positive status in only one patient. Carcinoembryonic antigen- and carbohydrate antigen19-9-positive status were significant prognostic factors for overall survival after recurrence, but the presence of serum p53 antibodies at recurrence was not. CONCLUSIONS: Postoperative serum p53 antibody status should only be followed in patients with preoperative-positive status. Carcinoembryonic antigen and carbohydrate antigen19-9 should be followed even in preoperative-negative patients. Unlike carcinoembryonic antigen- and carbohydrate antigen19-9-positive status, serum p53 antibody-positive status as recurrence was not a poor prognostic indicator.


Assuntos
Antígeno CA-19-9/sangue , Antígeno Carcinoembrionário/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos/sangue , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Feminino , Proteínas Ligadas por GPI/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Assistência Perioperatória , Prognóstico , Estudos Retrospectivos , Proteína Supressora de Tumor p53/imunologia
9.
Cancer Sci ; 110(8): 2573-2589, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31145522

RESUMO

To reduce unnecessary prostate biopsies (Pbx), better discrimination is needed. To identify clinically significant prostate cancer (CSPC) we determined the performance of LacdiNAc-glycosylated prostate-specific antigen (LDN-PSA) and LDN-PSA normalized by prostate volume (LDN-PSAD). We retrospectively measured LDN-PSA, total PSA (tPSA), and free PSA/tPSA (F/T PSA) values in 718 men who underwent a Pbx in 3 academic urology clinics in Japan and Canada (Pbx cohort) and in 174 PC patients who subsequently underwent radical prostatectomy in Australia (preop-PSA cohort). The assays were evaluated using the area under the receiver operating characteristics curve (AUC) and decision curve analyses to discriminate CSPC. In the Pbx cohort, LDN-PSAD (AUC 0.860) provided significantly better clinical performance for discriminating CSPC compared with LDN-PSA (AUC 0.827, P = 0.0024), PSAD (AUC 0.809, P < 0.0001), tPSA (AUC 0.712, P < 0.0001), and F/T PSA (AUC 0.661, P < 0.0001). The decision curve analysis showed that using a risk threshold of 20% and adding LDN-PSA and LDN-PSAD to the base model (age, digital rectal examination status, tPSA, and F/T PSA) permitted avoidance of even more biopsies without missing CSPC (9.89% and 18.11%, respectively vs 2.23% [base model]). In the preop-PSA cohort, LDN-PSA values positively correlated with tumor volume and tPSA and were significantly higher in pT3, pathological Gleason score ≥ 7. Limitations include limited sample size, retrospective nature, and no family history information prior to biopsy. LacdiNAc-glycosylated PSA is significantly better than the conventional PSA test in identifying patients with CSPC. This study was approved by the ethics committee of each institution ("The Study about Carbohydrate Structure Change in Urological Disease"; approval no. 2014-195).


Assuntos
Lactose/análogos & derivados , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Idoso , Glicosilação , Humanos , Lactose/metabolismo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores/métodos , Antígeno Prostático Específico , Curva ROC , Estudos Retrospectivos , Carga Tumoral/fisiologia
11.
Biochemistry ; 57(35): 5257-5269, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30091902

RESUMO

Discerning the different interaction states during dynamic protein-ligand binding is difficult. Here we apply site-specific cysteine-α-chloroacetyl cross-linking to scrutinize the binding between the Src homology 2 (SH2) domain and phosphotyrosine (pY) peptides, a highly dynamic interaction that is a key to cellular signal transduction. From a model SH2 protein to a set of representative SH2 domains, we showed here that a proximity-induced cysteine-α-chloroacetyl reaction cross-linked two spatially adjacent chemical groups as a result of the binding interaction, and reciprocally, the information about the interaction states can be deduced from the cross-linked products. To our surprise, we found SH2 domains can adopt a reverse binding mode with "single-pronged", "two-pronged", and "half" pY peptides. This finding was further supported by a set of 500 ns molecular dynamics simulations. This serendipitous finding defies the canonical theory of SH2 binding, suggests a possible answer about the source of the versatility of SH2 signaling, and sets a model for other protein binding interactions.


Assuntos
Fosfolipase C gama/metabolismo , Fosfopeptídeos/metabolismo , Fosfotirosina/metabolismo , Domínios de Homologia de src , Sequência de Aminoácidos , Sítios de Ligação , Humanos , Simulação de Dinâmica Molecular , Fosfolipase C gama/química , Fosfopeptídeos/química , Fosfotirosina/química , Ligação Proteica , Transdução de Sinais
12.
Anal Chem ; 90(23): 13876-13881, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30395435

RESUMO

A basic but critical step in targeted proteomics by mass spectrometry is the separation of the targeted proteins from the complex mixture of the whole proteome by affinity purification. The bait protein is usually immobilized on the surface of a solid support to enable affinity-based purification of the targeted proteome. Here, we developed a site-specific covalent immobilization of the bait protein through affinity-guided covalent coupling (AGCC) of a single cysteine residue of an SH2 domain (utilized as an affinity tag for the protein target) with an engineered ligand peptide. Site-specific covalent immobilization of a methyllysine-binding protein HP1ß chromodomain on the agarose resin was used to purify the methyllysine proteome from the whole-protein mixture. This new bait immobilization led to a notably low background in the affinity purification step, markedly outperforming the conventional (His)6 tag-nickel nitrilotriacetic acid (Ni-NTA) immobilization method. Subsequent analysis of the purified proteome identified 275 lysine methylated sites and 184 methylated proteins from 332 HP1ß CD-binding proteins, including 30 novel methylated proteins. This work demonstrates that a robust site-specific covalent protein immobilization method is well-suited for proteomic analysis of low-abundance proteins. This method also enables the identification of new methylated proteins and methylation sites in the methyllysine proteome.


Assuntos
Lisina/análogos & derivados , Lisina/isolamento & purificação , Proteoma/química , Proteoma/isolamento & purificação , Homólogo 5 da Proteína Cromobox , Humanos , Lisina/química , Células MCF-7 , Ácido Nitrilotriacético/análogos & derivados , Ácido Nitrilotriacético/química , Compostos Organometálicos/química , Peptídeos/química , Domínios de Homologia de src
14.
Nat Chem Biol ; 12(11): 959-966, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27642862

RESUMO

We present a new strategy for systematic identification of phosphotyrosine (pTyr) by affinity purification mass spectrometry (AP-MS) using a Src homology 2 (SH2)-domain-derived pTyr superbinder as the affinity reagent. The superbinder allows for markedly deeper coverage of the Tyr phosphoproteome than anti-pTyr antibodies when an optimal amount is used. We identified ∼20,000 distinct phosphotyrosyl peptides and >10,000 pTyr sites, of which 36% were 'novel', from nine human cell lines using the superbinder approach. Tyrosine kinases, SH2 domains and phosphotyrosine phosphatases were preferably phosphorylated, suggesting that the toolkit of kinase signaling is subject to intensive regulation by phosphorylation. Cell-type-specific global kinase activation patterns inferred from label-free quantitation of Tyr phosphorylation guided the design of experiments to inhibit cancer cell proliferation by blocking the highly activated tyrosine kinases. Therefore, the superbinder is a highly efficient and cost-effective alternative to conventional antibodies for systematic and quantitative characterization of the tyrosine phosphoproteome under normal or pathological conditions.


Assuntos
Fosfotirosina/metabolismo , Proteômica , Linhagem Celular Tumoral , Humanos , Espectrometria de Massas , Fosforilação , Fosfotirosina/química , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Domínios de Homologia de src
15.
Mol Cell Proteomics ; 15(10): 3270-3281, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27440912

RESUMO

The Src Homology-3 (SH3) domains are ubiquitous protein modules that mediate important intracellular protein interactions via binding to short proline-rich consensus motifs in their target proteins. The affinity and specificity of such core SH3 - ligand contacts are typically modest, but additional binding interfaces can give rise to stronger and more specific SH3-mediated interactions. To understand how commonly such robust SH3 interactions occur in the human protein interactome, and to identify these in an unbiased manner we have expressed 324 predicted human SH3 ligands as full-length proteins in mammalian cells, and screened for their preferred SH3 partners using a phage display-based approach. This discovery platform contains an essentially complete repertoire of the ∼300 human SH3 domains, and involves an inherent binding threshold that ensures selective identification of only SH3 interactions with relatively high affinity. Such strong and selective SH3 partners could be identified for only 19 of these 324 predicted ligand proteins, suggesting that the majority of human SH3 interactions are relatively weak, and thereby have capacity for only modest inherent selectivity. The panel of exceptionally robust SH3 interactions identified here provides a rich source of leads and hypotheses for further studies. However, a truly comprehensive characterization of the human SH3 interactome will require novel high-throughput methods based on function instead of absolute binding affinity.


Assuntos
Proteoma/análise , Quinases da Família src/química , Quinases da Família src/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Humanos , Ligantes , Biblioteca de Peptídeos , Ligação Proteica , Mapas de Interação de Proteínas , Proteoma/química , Domínios de Homologia de src
16.
Int J Mol Sci ; 18(2)2017 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-28134773

RESUMO

Wisteria floribunda agglutinin (WFA) preferably binds to LacdiNAc glycans, and its reactivity is associated with tumor progression. The aim of this study to examine whether the serum LacdiNAc carrying prostate-specific antigen-glycosylation isomer (PSA-Gi) and WFA-reactivity of tumor tissue can be applied as a diagnostic and prognostic marker of prostate cancer (PCa). Between 2007 and 2016, serum PSA-Gi levels before prostate biopsy (Pbx) were measured in 184 biopsy-proven benign prostatic hyperplasia patients and 244 PCa patients using an automated lectin-antibody immunoassay. WFA-reactivity on tumor was analyzed in 260 radical prostatectomy (RP) patients. Diagnostic and prognostic performance of serum PSA-Gi was evaluated using area under the receiver-operator characteristic curve (AUC). Prognostic performance of WFA-reactivity on tumor was evaluated via Cox proportional hazards regression analysis and nomogram. The AUC of serum PSA-Gi detecting PCa and predicting Pbx Grade Group (GG) 3 and GG ≥ 3 after RP was much higher than those of conventional PSA. Multivariate analysis showed that WFA-reactivity on prostate tumor was an independent risk factor of PSA recurrence. The nomogram was a strong model for predicting PSA-free survival provability with a c-index ≥0.7. Serum PSA-Gi levels and WFA-reactivity on prostate tumor may be a novel diagnostic and pre- and post-operative prognostic biomarkers of PCa, respectively.


Assuntos
Biomarcadores Tumorais/sangue , Lectinas de Plantas/metabolismo , Polissacarídeos/metabolismo , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Receptores de N-Acetilglucosamina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biópsia , Glicosilação , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Prognóstico , Próstata/patologia , Próstata/cirurgia , Antígeno Prostático Específico/sangue , Prostatectomia , Hiperplasia Prostática/sangue , Hiperplasia Prostática/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Curva ROC , Fatores de Risco
17.
Trends Biochem Sci ; 36(4): 183-90, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21227701

RESUMO

An important question in modular domain-peptide interactions, which play crucial roles in many biological processes, is how the diverse specificities exhibited by different members of a domain family are encoded in a common scaffold. Analysis of the Src homology (SH) 2 family has revealed that its specificity is determined, in large part, by the configuration of surface loops that regulate ligand access to binding pockets. In a distinct manner, SH3 domains employ loops for ligand recognition. The PDZ domain, in contrast, achieves specificity by co-evolution of binding-site residues. Thus, the conformational and sequence variability afforded by surface loops and binding sites provides a general mechanism by which to encode the wide spectrum of specificities observed for modular protein interaction domains.


Assuntos
Domínios e Motivos de Interação entre Proteínas , Proteínas/química , Humanos , Ligantes , Modelos Moleculares , Especificidade por Substrato
18.
Anal Chem ; 87(3): 1797-803, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25546230

RESUMO

A high-sensitivity immunoassay system with surface plasmon field-enhanced fluorescence spectrometry (SPFS) was constructed using a plastic sensor chip and then applied to the detection of total prostate-specific antigen (total PSA) and GalNAcß1-4GlcNAc-linked prostate-specific antigen (LacdiNAc-PSA) in serum, to discriminate between prostate cancer (PC) and benign prostate hyperplasia (BPH). By using this automated SPFS immunoassay, the detection limit for total PSA in serum was as low as 0.04 pg/mL, and the dynamic range was estimated to be at least five digits. A two-step sandwich SPFS immunoassay for LacdiNAc-PSA was constructed using both the anti-PSA IgG antibody to capture PSA and Wisteria floribunda agglutinin (WFA) for the detection of LacdiNAc. The results of the LacdiNAc-PSA immunoassay with SPFS showed that the assay had a sensitivity of 20.0 pg/mL and permitted the specific distinction between PC and BPH within the PSA gray zone. These results suggested that high-sensitivity automated SPFS immunoassay systems might become a powerful tool for the diagnosis of PC and other diseases.


Assuntos
Imunoensaio/instrumentação , Lactose/análogos & derivados , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Desenho de Equipamento , Humanos , Lactose/análise , Lactose/sangue , Limite de Detecção , Masculino , Antígeno Prostático Específico/análise , Neoplasias da Próstata/sangue , Espectrometria de Fluorescência/instrumentação
19.
Genome Res ; 22(7): 1222-30, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22194470

RESUMO

Phosphotyrosine (pTyr) signaling, which plays a central role in cell-cell and cell-environment interactions, has been considered to be an evolutionary innovation in multicellular metazoans. However, neither the emergence nor the evolution of the human pTyr signaling system is currently understood. Tyrosine kinase (TK) circuits, each of which consists of a TK writer, a kinase substrate, and a related reader, such as Src homology (SH) 2 domains and pTyr-binding (PTB) domains, comprise the core machinery of the pTyr signaling network. In this study, we analyzed the evolutionary trajectories of 583 literature-derived and 50,000 computationally predicted human TK circuits in 19 representative eukaryotic species and assigned their evolutionary origins. We found that human TK circuits for intracellular pTyr signaling originated largely from primitive organisms, whereas the inter- or extracellular signaling circuits experienced significant expansion in the bilaterian lineage through the "back-wiring" of newly evolved kinases to primitive substrates and SH2/PTB domains. Conversely, the TK circuits that are involved in tissue-specific signaling evolved mainly in vertebrates by the back-wiring of vertebrate substrates to primitive kinases and SH2/PTB domains. Importantly, we found that cancer signaling preferentially employs the pTyr sites, which are linked to more TK circuits. Our work provides insights into the evolutionary paths of the human pTyr signaling circuits and suggests the use of a network approach for cancer intervention through the targeting of key pTyr sites and their associated signaling hubs in the network.


Assuntos
Evolução Molecular , Neoplasias/metabolismo , Fosfotirosina/metabolismo , Transdução de Sinais , Animais , Comunicação Celular , Membrana Celular/genética , Membrana Celular/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , Humanos , Modelos Genéticos , Neoplasias/genética , Especificidade de Órgãos , Fosforilação , Fosfotirosina/classificação , Fosfotirosina/genética , Filogenia , Ligação Proteica , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Domínios de Homologia de src
20.
Proc Natl Acad Sci U S A ; 109(5): 1455-60, 2012 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-22307599

RESUMO

The epithelial growth factor receptor plays an important role in cell migration and cancer metastasis, but the underlying molecular mechanism is not fully understood. We show here that differential regulation of the Ras-homology-GTPase-activating protein [corrected] (Rho-GAP) activity of deleted in liver cancer 1 (DLC1) by tensin3 and COOH-terminal tensin-like protein (cten) controls EGF-driven cell migration and transformation. Tensin3 binds DLC1 through its actin-binding domain, a region that is missing in cten, and thereby releases an autoinhibitory interaction between the sterile alpha motif and Rho-GAP domains of DLC1. Consequently, tensin3, but not cten, promotes the activation of DLC1, which, in turn, leads to inactivation of RhoA and decreased cell migration. Depletion of endogenous tensin3, but not cten, augmented the formation of actin stress fibers and focal adhesions and enhanced cell motility. These effects were, however, ablated by an inhibitor of the Rho-associated protein kinase. Importantly, activation of DLC1 by tensin3 or its actin-binding domain drastically reduced the anchorage-independent growth of transformed cells. Our study therefore links dynamic regulation of tensin family members by EGF to Rho-GAP through DLC1 and suggests that the tensin-DLC1-RhoA signaling axis plays an important role in tumorigenesis and cancer metastasis, and may be explored for cancer intervention.


Assuntos
Movimento Celular/fisiologia , Transformação Celular Neoplásica , Proteínas Ativadoras de GTPase/fisiologia , Proteínas dos Microfilamentos/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Actinas/metabolismo , Linhagem Celular Tumoral , Adesões Focais , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Microscopia Confocal , Tensinas , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
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